Fix Authentication & Dashboard Issues in Next.js App + Deploy

We have an existing small SaaS web application built with Next.js, TypeScript, Node.js/Express, Prisma and PostgreSQL. We need a developer to fix a few issues before deploying the latest version to production. Current Issues Frontend After login, the dashboard sometimes doesn't load the user information correctly. One dashboard API request is being triggered multiple times. There is a small responsive issue on the dashboard for mobile screens. Backend The user profile endpoint occasionally returns an unauthorized response after login. Authentication/session handling needs to be checked. One API response needs better error handling. Database Review the relevant Prisma query and PostgreSQL relation. Make sure the correct user data is returned after authentication. Deployment Once the application is working correctly locally: Deploy the Next.js frontend to Vercel Deploy the Node.js/Express backend to Render Configure production environment variables Connect the existing PostgreSQL database Resolve any CORS/environment configuration issues Verify the complete production flow Requirements Please do not rewrite the application or change the existing architecture. The goal is to identify the root causes, make focused fixes, test them locally, and deploy the corrected version. Tech stack: Next.js React TypeScript Node.js Express.js Prisma PostgreSQL Vercel Render Git/GitHub Budget: $80 fixed Please include examples of similar full-stack debugging/deployment work in your proposal.